Well, well... What if it flaps back and forth? :-)

--
Marko Milivojevic - CCIE #18427 (SP R&S)
Senior CCIE Instructor - IPexpert

On Fri, Oct 12, 2012 at 12:06 AM, vin.ccie29412 <[email protected]> wrote:
>  peering to an hsrp vip will work  ,  fast hellos can be used to minimise
> the swap delay , in all circumstances bgp will flap .
>
> to have device redundancy to a single upstream pe would sound over spec ,
> but to a multi node internal external peer would be ideal . A Flap is much
> better than total loss of service .
>
> Regards
>
> Vin
>
>
>
>
> On Fri, Oct 12, 2012 at 5:47 AM, Marko Milivojevic <[email protected]>wrote:
>
>> To be honest, I'm as amused as you are with this :-). I'm in a
>> bootcamp for the next three weeks, but I'll for sure give it a
>> thorough test when I'm done :-).
>>
>> I'm guessing it can be made to work, as long as HSRP-side is
>> "passive", i.e. not the one initiating connection. Of course, without
>> a state exchange between HSRP peers, when there is HSRP failover, BGP
>> will flap. This is probably why it's not recommended.
>>
>> --
>> Marko Milivojevic - CCIE #18427 (SP R&S)
>> Senior CCIE Instructor - IPexpert
>>
>> On Thu, Oct 11, 2012 at 5:16 PM, Nick Bonifacio <[email protected]>
>> wrote:
>> > There has to be instability issues, right?  Flapping, arps and macs
>> getting hosed perhaps?
>> >
>> > *Paging Dr. Marko*
>> >
>> >
>> > ________________________________
>> >  From: Tony Singh <[email protected]>
>> > To: Nick Bonifacio <[email protected]>
>> > Cc: Bob McCouch <[email protected]>; "[email protected]" <
>> [email protected]>
>> > Sent: Thursday, October 11, 2012 6:13 PM
>> > Subject: Re: [OSL | CCIE_RS] Hello team can we make bgp neighbor ship
>> HSRP virtual IP ?
>> >
>> >
>> > Good work Nick
>> >
>> > I'm sure Cisco know this works..? Why do they not recommend it then ...
>> >
>> >
>> > --
>> > BR
>> >
>> > Tony
>> > Sent from my iPhone on 3
>> >
>> > On 11 Oct 2012, at 23:06, Nick Bonifacio <[email protected]> wrote:
>> >
>> >
>> >
>> >>
>> >>R5(config-router)#do sh ip b
>> >>*Oct 11 22:09:20.495: %BGP-5-ADJCHANGE: neighbor 10.0.46.1 Down User
>> reset
>> >>*Oct 11 22:09:20.907: %BGP-5-ADJCHANGE: neighbor 10.0.46.1 Up gp
>> >>BGP table version is 16, local router ID is 10.0.46.55
>> >>Status codes: s suppressed, d damped, h history, * valid, > best, i -
>> internal,
>> >>              r RIB-failure, S Stale
>> >>Origin codes: i - IGP, e - EGP, ? - incomplete
>> >>
>> >>
>> >>   Network          Next Hop            Metric LocPrf Weight Path
>> >>*>i192.46.1.0       10.0.46.1             1234    100  10000 i
>> >>*>i192.46.2.0       10.0.46.1             1234    100  10000 i
>> >>*>i192.46.3.0       10.0.46.1             1234    100  10000 i
>> >>*>i192.46.4.0       10.0.46.1             1234    100  10000 i
>> >>*>i192.46.5.0       10.0.46.1             1234    100  10000 i
>> >>*>i192.46.6.0       10.0.46.1             1234    100  10000 i
>> >>*>i192.46.7.0       10.0.46.1             1234    100  10000 i
>> >>*>i192.46.8.0       10.0.46.1             1234    100  10000 i
>> >>*>i192.46.9.0       10.0.46.1             1234    100  10000 i
>> >>*>i192.46.10.0      10.0.46.1             1234    100  10000 i
>> >>*>i192.46.11.0      10.0.46.1             1234    100  10000 i
>> >>*>i192.46.12.0      10.0.46.1             1234    100  10000 i
>> >>*>i192.46.13.0      10.0.46.1             1234    100  10000 i
>> >>*>i192.46.14.0      10.0.46.1             1234    100  10000 i
>> >>*>i192.46.15.0      10.0.46.1             1234    100  10000 i
>> >>R5(config-router)#
>> >>
>> >>
>> >>i need a fast way to copy and paste prefixes in  :)
>> >>
>> >>
>> >>I did manipulate weight, MED...
>> >>
>> >>________________________________
>> >> From: Tony Singh <[email protected]>
>> >>To: Nick Bonifacio <[email protected]>
>> >>Cc: Bob McCouch <[email protected]>; "[email protected]" <
>> [email protected]>
>> >>Sent: Thursday, October 11, 2012 5:54 PM
>> >>Subject: Re: [OSL | CCIE_RS] Hello team can we make bgp neighbor ship
>> HSRP virtual IP ?
>> >>
>> >>Take it further see how many prefixes it can handle, check metrics work
>> weight local pref med...
>> >>
>> >>--
>> >>BR
>> >>
>> >>Tony
>> >>
>> >>Sent from my iPad
>> >>
>> >>On 11 Oct 2012, at 22:34, Nick Bonifacio <[email protected]> wrote:
>> >>
>> >>> I can't believe it, working on real hardware as well:
>> >>>
>> >>> interface FastEthernet0/0
>> >>>  ip address 10.0.46.6 255.255.255.0
>> >>>  duplex auto
>> >>>  speed auto
>> >>>  standby 0 ip 10.0.46.1
>> >>>
>> >>>
>> >>> router bgp 456
>> >>>  no synchronization
>> >>>  bgp log-neighbor-changes
>> >>>  neighbor 10.0.46.55 remote-as 456
>> >>>  no auto-summary
>> >>>
>> >>>
>> >>> ------------------------------------------------------------------
>> >>>
>> >>>
>> >>> interface FastEthernet0/0
>> >>>  ip address 10.0.46.55 255.255.255.0
>> >>>  duplex
>> >  auto
>> >>>  speed auto
>> >>>
>> >>>
>> >>> router bgp 456
>> >>>  no synchronization
>> >>>  bgp log-neighbor-changes
>> >>>  neighbor 10.0.46.1 remote-as 456
>> >>>  no auto-summary
>> >>>
>> >>>
>> >>> R5(config-router)#do sh ip bgp sum
>> >>> BGP router identifier 10.0.46.55, local AS number 456
>> >>> BGP table version is 1, main routing table version 1
>> >>>
>> >>> Neighbor        V          AS MsgRcvd MsgSent   TblVer  InQ OutQ
>> Up/Down  State/PfxRcd
>> >>> 10.0.46.1       4          456       5             5       1         0
>>              0 00:03:18        0
>> >>>
>> >>>
>> >>> R5(config-router)#do sh tcp brief
>> >>> TCB       Local Address
>> >                  Foreign Address             (state)
>> >>> 66A1041C       10.0.46.55.39341            10.0.46.1.179
>>   ESTAB
>> >>>
>> >>>
>> >>> System image file is "flash:c1841-adventerprisek9-mz.124-24.T7.bin"
>> >>>
>> >>>
>> >>>
>> >>> ________________________________
>> >>> From: Nick Bonifacio <[email protected]>
>> >>> To: Bob McCouch <[email protected]>
>> >>> Cc: "[email protected]" <[email protected]>
>> >>> Sent: Thursday, October 11, 2012 8:51 AM
>> >>> Subject: Re: [OSL | CCIE_RS] Hello team can we make bgp neighbor ship
>> HSRP virtual IP ?
>> >>>
>> >>> Just what I need, another OCD day.  Oh well, I'll be home in about 8
>> hours and will have access to real hardware.  I will let everyone know what
>> happens.
>> >>>
>> >>> Nick
>> >>>
>> >>> Sent from my iPhone
>> >>>
>> >>> On Oct 11, 2012, at 8:43 AM, Bob McCouch <[email protected]> wrote:
>> >>>
>> >>>> Interesting. I was also pretty sure that didn't work. At best it would
>> >>>> only do a passive open (respond to a TCP syn) no originate the
>> >>>> session.
>> >>>>
>> >>>> Bob
>> >>>> --
>> >>>> Sent from my iPhone, please excuse any typos.
>> >>>>
>> >>>> On Oct 11, 2012, at 8:25 AM,
>> >  Nick Bonifacio <[email protected]> wrote:
>> >>>>
>> >>>>> //Disclaimer:  I am using GNS3 for this example.
>> >>>>>
>> >>>>> This is the way I understand it, anyone else feel free to chime in:
>> >>>>>
>> >>>>> Think update source.
>> >>>>>
>> >>>>> router bgp 4
>> >>>>> neighbor 10.0.4.5 remote-as 5
>> >>>>> neighbor 10.0.4.5 update-source FastEthernet0/0
>> >>>>>
>> >>>>>
>> >>>>> interface FastEthernet0/0
>> >>>>> ip address 10.0.4.4 255.255.255.0
>> >>>>> duplex auto
>> >>>>> speed auto
>> >>>>> standby 0 ip 10.0.4.254
>> >>>>>
>> >>>>> how can I create a neighborship by sourcing the standby 0 IP?  I
>> can't.
>> >>>>>
>> >>>>> Let's look at router 5 on the other side
>> >>>>>
>> >>>>> interface
>> >  FastEthernet0/0
>> >>>>> ip address 10.0.4.5 255.255.255.0
>> >>>>> duplex auto
>> >>>>> speed auto
>> >>>>>
>> >>>>> router bgp 5
>> >>>>> no synchronization
>> >>>>> bgp log-neighbor-changes
>> >>>>> neighbor 10.0.1.1 remote-as 1
>> >>>>> neighbor 10.0.4.254 remote-as 4
>> >>>>> no auto-summary
>> >>>>>
>> >>>>>
>> >>>>> Let's debug BGP on R4
>> >>>>>
>> >>>>> R4(config-router)#no
>> >>>>> *Mar  1 00:31:36.267: BGP: 10.0.4.5 passive open to 10.0.4.254
>> >>>>> *Mar  1 00:31:36.271: BGP: 10.0.4.5 passive open failed - 10.0.4.254
>> is not update-source FastEthernet0/0's address (10.0.4.4)
>> >>>>> *Mar  1 00:31:36.271: BGP: 10.0.4.5 remote connection attempt
>> failed, local address 10.0.4.254
>> >>>>> R4(config-router)#no
>> >>>>> *Mar  1 00:31:38.255: BGP: 10.0.4.5 open active, local address
>> >  10.0.4.4
>> >>>>> *Mar  1 00:31:38.311: BGP: 10.0.4.5 open failed: Connection refused
>> by remote host, open active delayed 26388ms (35000ms max, 28% jitter)
>> >>>>> R4(config-router)#no
>> >>>>>
>> >>>>> ok it is complaining about 10.0.4.254 not being fa0/0's address.
>>  Fine, I will remove update source fa0/0
>> >>>>>
>> >>>>>
>> >>>>>
>> >>>>> router bgp 4
>> >>>>> no synchronization
>> >>>>> bgp log-neighbor-changes
>> >>>>> neighbor 10.0.4.2 remote-as 2
>> >>>>> neighbor 10.0.4.3 remote-as 3
>> >>>>> neighbor 10.0.4.5 remote-as 5
>> >>>>> neighbor 10.0.4.5 update-source FastEthernet0/0
>> >>>>> maximum-paths 3
>> >>>>> no auto-summary
>> >>>>>
>> >>>>> no neighbor 10.0.4.5 update-source FastEthernet0/0
>> >>>>>
>> >>>>> BGP: 10.0.4.5 rcvd OPEN w/ remote AS 5
>> >>>>> *Mar  1
>> >  00:33:09.427: BGP: 10.0.4.5 went from OpenSent to OpenConfirm
>> >>>>> *Mar  1 00:33:09.427: BGP: 10.0.4.5 send message type 1, length
>> (incl. header) 45
>> >>>>> *Mar  1 00:33:09.475: BGP: 10.0.4.5 went from OpenConfirm to
>> Established
>> >>>>> *Mar  1 00:33:09.475: %BGP-5-ADJCHANGE: neighbor 10.0.4.5 Up
>> >>>>>
>> >>>>> uh oh, it is working!  Interesting.. I am in GNS3 but will lab it up
>> at home on real hardware once I get there.  This is not the behavior I
>> expected.
>> >>>>>
>> >>>>> R5#sh ip bgp sum
>> >>>>> [...]
>> >>>>> Neighbor        V    AS MsgRcvd MsgSent   TblVer  InQ OutQ Up/Down
>>  State/PfxRcd
>> >>>>> 10.0.1.1        4     1      40      40        2    0    0 00:36:01
>> >  1
>> >>>>> 10.0.4.254      4     4      16      22        2    0    0 00:02:47
>>        1
>> >>>>>
>> >>>>>
>> >>>>> I also tested it with iBGP and the same behavior occured.  I also
>> failed over the HSRP address and made another node active as 10.0.4.254 and
>> the adjacency did come back up on that router!
>> >>>>>
>> >>>>> I will try this out on real hardware once I get home and then report
>> back.  We had tried this in production 2 months ago using ASR1000s and
>> could not get it working.
>> >>>>>
>> >>>>> Nick
>> >>>>>
>> >>>>>
>> >>>>> ________________________________
>> >>>>> From: Samir Idris <[email protected]>
>> >>>>> To: Nick Bonifacio <[email protected]>
>> >>>>> Cc: Taqdir Singh <[email protected]>; "
>> [email protected]" <[email protected]>
>> >>>>> Sent: Thursday, October 11, 2012 7:50 AM
>> >>>>> Subject: Re: [OSL | CCIE_RS] Hello team can we make bgp neighbor
>> ship HSRP virtual IP ?
>> >>>>>
>> >>>>>
>> >>>>> Nick,
>> >>>>>
>> >>>>> Why cant we source from a virtual IP?  Can you shed some light on
>> the logic?
>> >>>>>
>> >>>>> Regards,
>> >>>>> Samir.
>> >>>>>
>> >>>>> On Thursday, October 11, 2012, Nick
>> >  Bonifacio <[email protected]> wrote:
>> >>>>>> Hi Taqdir,
>> >>>>>>
>> >>>>>> You have to source from a physical interface and cannot source from
>> a vIP.  Here is a link to "best practice" using HSRP and multihomed BGP
>> environments:
>> >>>>>>
>> >>>>>>
>> http://www.cisco.com/en/US/tech/tk365/technologies_configuration_example09186a0080093f2c.shtml
>> >>>>>>
>> >>>>>>
>> >>>>>> Thanks!
>> >>>>>> Nick
>> >>>>>>
>> >>>>>> ________________________________
>> >>>>>> From: Taqdir Singh <[email protected]>
>> >>>>>> To: [email protected]
>> >>>>>> Sent: Thursday, October 11, 2012 3:16 AM
>> >>>>>> Subject: [OSL | CCIE_RS] Hello team can we make bgp neighbor ship
>> HSRP virtual IP ?
>> >>>>>>
>> >>>>>> Hello team can we make bgp neighborship with HSRP virtual IP ?
>> >>>>>> _______________________________________________
>> >>>>>> For more information regarding industry leading CCIE Lab training,
>> please visit http://www.ipexpert.com/
>> >>>>>>
>> >>>>>> Are you a CCNP or CCIE and looking for a job? Check out
>> http://www.platinumplacement.com/
>> >>>>>>
>> >>>>>> http://onlinestudylist.com/mailman/listinfo/ccie_rs
>> >>>>>> _______________________________________________
>> >>>>>> For more information regarding industry leading CCIE Lab training,
>> please visit http://www.ipexpert.com/
>> >>>>>>
>> >>>>>> Are you a CCNP or CCIE and looking for a job? Check out
>> http://www.platinumplacement.com/
>> >>>>>>
>> >>>>>> http://onlinestudylist.com/mailman/listinfo/ccie_rs
>> >>>>>
>> >>>>> --
>> >>>>> Samir Idris
>> >>>>> _______________________________________________
>> >>>>> For more information regarding industry leading CCIE Lab training,
>> please visit www.ipexpert.com
>> >>>>>
>> >>>>> Are
>> >  you a CCNP or CCIE and looking for a job? Check out
>> www.PlatinumPlacement.com
>> >>>>>
>> >>>>> http://onlinestudylist.com/mailman/listinfo/ccie_rs
>> >>> _______________________________________________
>> >>> For more information regarding industry leading CCIE Lab training,
>> please visit www.ipexpert.com
>> >>>
>> >>> Are you a CCNP or CCIE and looking for a job? Check out
>> www.PlatinumPlacement.com
>> >>>
>> >>> http://onlinestudylist.com/mailman/listinfo/ccie_rs
>> >>> _______________________________________________
>> >>> For more information regarding industry leading CCIE Lab training,
>> please visit www.ipexpert.com
>> >>>
>> >>> Are you a CCNP or CCIE and looking for a job? Check out
>> www.PlatinumPlacement.com
>> >>>
>> >>> http://onlinestudylist.com/mailman/listinfo/ccie_rs
>> >>
>> >>
>> >>
>> > _______________________________________________
>> > For more information regarding industry leading CCIE Lab training,
>> please visit www.ipexpert.com
>> >
>> > Are you a CCNP or CCIE and looking for a job? Check out
>> www.PlatinumPlacement.com
>> >
>> > http://onlinestudylist.com/mailman/listinfo/ccie_rs
>> _______________________________________________
>> For more information regarding industry leading CCIE Lab training, please
>> visit www.ipexpert.com
>>
>> Are you a CCNP or CCIE and looking for a job? Check out
>> www.PlatinumPlacement.com
>>
>> http://onlinestudylist.com/mailman/listinfo/ccie_rs
>>
> _______________________________________________
> For more information regarding industry leading CCIE Lab training, please 
> visit www.ipexpert.com
>
> Are you a CCNP or CCIE and looking for a job? Check out 
> www.PlatinumPlacement.com
>
> http://onlinestudylist.com/mailman/listinfo/ccie_rs
_______________________________________________
For more information regarding industry leading CCIE Lab training, please visit 
www.ipexpert.com

Are you a CCNP or CCIE and looking for a job? Check out 
www.PlatinumPlacement.com

http://onlinestudylist.com/mailman/listinfo/ccie_rs

Reply via email to